Automatic electric window guard



Nov. 6 1923. r 1,472,864-

w. F. BURNS AUTOMATIC ELECTRIC WINDOW GUARD Filed May 24, 1922 2 Sheets-Sheet 1 55' 9 awoamkou Nov. 6,1923. 1,472,864

' W. F. BURNS AUTOMATIC ELECTRIC WINDOW GUARD Filed May 24. 1922 2 Sheets-Sheet 2 E) wuantozj- [025134222 it fizz/"22s.

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Patented Nov. 6, 1923.

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WILLIAM E. BURNS, or. MEMPHIS, TENNESSEE. V 1

AUTOMATIC ELEo'rnro w rNnow GUARD.

Application filed Ma 24,

To all whom it may concern: 7

Be it known that I, TViLLI'AM F. BURNS,

a citizen of the United States, and residing I at Memphis, in the county of Shelby and State of Tennessee, have invented certain new and useful Improvements in Automatic Electric Window Guards, of which the following is a specification. I

This invention relates to automatic electric window guards, or apparatus for use in connection with display windows, and the primary object thereof is to provide an appliance of this class designed particularly for use in connection with the display windows of merchants, or traders dealing in jewelry, precious stones, furs or light merchandise, and which is particularly designed to prevent the theft or stealing of such merchandise by the breaking, cutting out or otherwise removing a portion of the window and the insertion of a hand therethrough.

It is a well known fact that in the use'of display windows of the class Specified,"valuable jewelry, precious stones and the like are within easy reach of any person who breaks or cuts out a portion of the glass, and a further object of this invention is to provide a guard which will be thrown into protecting position and prevent the removal of the merchandise in the window upon breakage of the glass.

A still further object is the provision of a guard for display windows which will be operated by electrical means, upon the breakage of the glass of said window.

Another object of the invention is to provide means on the glass of the display window whereby upon breakage of the glass one electrical circuit is broken and another circuit simultaneously made whereby the guard is thrown into protecting position.

Further objects and advantages of this inventicn will be apparent from the following specification when taken in conjunction with the accompanying drawings forming a part thereof.

In the drawings:

Figure l is an elevation of the device, partly in section shown with a display window;

Fig. 2 is an end view, in section, of the device applied to a display window;

Fig. 3 is a fragmentary view, partly in section of the device in elevated position; and

Fig. 4 is a detail sectional view of a por- 1922. Serial No. 563,462.

tion of the device in raised position showing the retaining means therefor.

Referring more particularlyto the drawings, 1 indicates the glass of a display window, which is secured within the usual frame 2; the display window having a floor 3 and being supported by the customary base or foundation 4.

said grating, which has wire mesh or the like 9 secured thereto in any suitable man- 'ner. The upper cross bar 10 of grating has its ends retained within the channelbars 5 as will be obvious.

Secured to the grating 8 at opposite sides thereof are rack bars 11 and 12, respectively, said rack bars having the teeth removed at the lower ends thereof for a substantial distance, as shown at 12.

Mounted beneath the floor? of the window in any suitable manner and substantially midway of the grating is an electric motor 13 having outwardly extending Shafts 14, mounted in bearings 15, said shafts carrying near their ends pinions 16, which pinions mesh with the upper ends of rack bars 11 and 12. p 7

As shown more clearly in Figs. 2 and 4, the floor 3 of the window is provided with. an opening 17 extending substantially the entire length of the window and normally covered with a gate 18 hinged at 19 to Said floor 3, the gate being formed preferably of sheet metal or the like.

For the purpose of retaining the grating in elevated position a Spring pressed stop 20 is provided which is secured in any suitable manner to the base 4, as illustrated in Fig. 4, said stop being adapted to expand and support the grating by receiving the lower end of one of the uprights 8 of the grating when the grating is in elevated position.

The numeral 21 denotes a conductor Secured to the glass 1 and forming part of a control for relay circuit, conductor 21 being tinfoil or the like. It is obvious that suitable advertising may be employed asa con ductor as is wellknown in the art;

A wire 22 leads from one end of conductor 21 to a battery 23 (the positive side thereof) and the other end of conductor 21 is connected to one terminal 24 of a re'lay 25, by a wire 26. The other terminal 27 ofthe relay is connected to the battery 23 j' wire 28.

The control circuit just described, it is obvious, is as follows: From thebattery23 through 22, thence through'21 to 26, through relay and its terminals 24 ancl.2,7, and back to the battery through wire 28.

Associated with this device is afrnagnetic conta tor of customary constructionfhaying terminals 29, terminals 30 anda switch a'rm 31, the circuit through said contactor being as follows: From the battery 23'through wire 22 to wire 32, thence through terminals 29, wires 33 and 3th, through terminalsj35f of relay 25, and back to the battery through wires 36 and 28. I

When the circuit just mentioned i thrown into operation, as will be hereinafter described, the switch arm 31 of themagnet-ic contactor will contact with terminals 30 thereof, and bring into operation the main or power circuit, which is as fo-llowsz-From the battery 23 through wire 37 to, and through switch 38 (which latter in the inoperative position of the grating normal. holds the main circuit closed), then through wire 39 to the motor 13, from the motor through 40, then throughterminals 30 and switch arm 31, back to the battery through wires 11 and 28.

A circuit is associated with this device which is adapted to set into operation an audible alarm such as a bell or the like 42, the circuit therefore being as followszFrom the battery 23 through 37 and 43 to the bell 12, from the bell through 4 1 to the terminals 35 of the relay 25 and back to the battery through 36 and 28. i

In normal position, the grating is retained as shown more clearly in Fig. 2, and should the glass 1 be broken or a piece crossed by conductor 21 removed therefrom in any manner the control circuit above mentioned wil be broken, it is obvious, thus permitting arm 45 of the relay 25 to drop and contact with terminals 35 which will set into operation the circuit through the other magnetic contact-or, which latter circuit will place switch arm 31 of the magnetic contactor into contact with, terminals 30.

Upon this latest operation themotor 13 will be energized because of the factthat the withtheir pinions 16, the rotation of said 'pin'lons 'servmg to elevate the grating due to the connection of rack bars 11 and 12 therewith. When the grating has been raised into protecting position, a detail of which is showfn'in Fig. 3, the push butt-on of switch 38 will engage in a recess 46 at the lower end of rack bar 11, and the motor circuit will be broken and the motor stopped.

" When the grating is being e'evated into protecting position" the upper edge thereof lwill strike gate 18 and swing the same on its pivot 19. VJhen the grating has reached its uppermost position, the teeth of the rack bars 11 and 12 will be out of mesh with the teeth of 'pinions 16, and the grating will be retained in elevated position by the expansion'of, the spring pressed stop 20 which will engage the lower end of the uprights 8.

After the motor circuit has been broken and the motor stopped, the audible alarm circuit is still in operation, and the alarm being sounded to warn outsiders of the fact that the. window glass 1 has-been tampered with.

lVhat I c aim is:

1. An automatic guard for display windows, comprising a' grating movable within said window, a motor for moving said grating, a control circuit, a power circuit connected to said motor, means for setting into operation the power circuit upon breaking of the control circuit, and automatic means for breaking the power circuit.

2. An automatic guard for display windows comprising a vertically movable grating, rack bars secured thereto, a motor connected with said rack barsand adapted to elevate said grating, a control circuit connected with the glass of the display window, a power circuit connected with said motor and adapted to be brought into operation upon the breaking of the control circuit, automatic means for breaking the power circuit upon the elevation of said grating, means for retaining the grating in elevated position, and an audible alarm circuit adapted to be brought into operation upon the breaking of the control circuit.

In testimony whereof I affix my signature.

WILLIAM F. BURNS. 

